Piston ring



April 7, 1925. 1,532,547

J. E. PRUYN PISTON RING Filed Nov. 17, 1919 WITNESS: a g INVENTOR.

l/ 4?) ATTORNEYJ.

Patented Apr. 7, 1925.

UNITED STATES JOHN ERNEST PRUYN, OF NEW YORK. N. Y.

PISTON RING.

Application filed November 17, 1919. Serial No. 338,488.

To all whom it may concern:

Be it known that I, Join: ERNEST PRUYN, a citizen of the United States, residing at the city of New York. in the borough of (Queens and State of New York, have invented certain new. and useful Improvements in Piston Rings, of which the following is a full, clear, and exact description.

This invention relates to piston rings especially adapted for engines, pumps and similar apparatus.

The object of the invention is to provide a joint for the piston ring which will be liquid and gas tight under all conditions of wear, which will prevent the end of the ring from projecting outward to engage the edge of a port that may enter the wall of the cylinder and also to produce a joint of this character'which can be easily and cheaply manufactured.

The invention will be described in detail with reference to the accompanying drawing. in which Fig. 1 illustrates in perspective the two ends of a transversely separated piston ring;

Fig. 2 is an end view of each of said ends;

Fig. 3 is a perspective view of one end of a ring in which the joint is of a modified nature;

Fig. 4 is an endview of said end;

Fig. 5 is a view of a completed ring showing a joint of the character of Fig. 1 as it appears when closed;

Fig. 6 is a similar View of the joint of the character shown in Fig. 3, and

Fig. 7 is a view of the joint of Fig. 5 shown partially open.

Referring first to the form shown in Figs. 1, 2 and 5, at the usual transverse opening of the ring I provide a modification of the usual and well known stepped joint, but instead of the usual three rectangular surfaces arranged to form a step I provide essentially on each end of the ring two inclined surfaces a and 6. These surfaces incline transversely of the ring and in opposite directions to each other, both of them beginning approximately at a median line, as c, on one of the vertical faces, as d, of the ring, and extending therefrom, one, as a, to the upper opposite corner of the ring at e, while the other, as b, to the lower opposite corner at f. These surfaces --are arranged similarly on both ends of the ring except that the inclined surfaces face in opposite directions respectively, so that when the two ends are overlapped and joined, in the manner shown in Fig. 5, the inclined face a of one end will rest against the corresponding face a of the other end and likewise the-inclined face I) will.

rest against the inclined face I) of the other end. The two surfaces are also preferably disposed in different transverse sections of the ring,'as shown, so that the rings will not be weakened too greatly because of the portion cut away to form the oblique surfaces. When the ring is seated in the groove of the piston and the joint closed as in Fig. 5, it will be seen that any radial movement of either end, whether it be an inward movement or an outward movement, will be opposed by the other, end, the inclined surfaces causing the ends to slide upward or downward until they encounter the upper or lower wall of the groove whereupon all further movement or displacement is prevented. Thus it becomes impossible for either of the ends to project beyond the face of the piston and thereby possibly enter a port and engage the shoulder thereof during the stroke of the piston.

In the case of the ordinary stepped joint, when the ring wears sufficiently to permit the joint to slighty open, two orifices are presented at the joint, through one of which gas and oil can pass to the back of the ring and thence out through the other, and thus escape past the ring. This is impossible in the joint described herein, for it will be seen that when the ring is permitted to expand by reason of wear of its outer periphery, the two orifices that are then presented in the outer face of the ring at the joint do not extend entirely to the back of the ring but are intercepted and maintained closed by the inclined surfaces, in the manner indicated, for instance by the exposed portions of the inclined surfaces a and b in Fig. 7. No matter to what extent the joint opens, so long as it does not fully separate, the inclined walls will act as dams to prevent the entrance of oil or gas to the space behind the ring and the joint will always remain right. It is furthermore pointed out that while there are other ways of forming these dams in the joint, as for instance, by means of rectangular walls as distinguished from inclined walls, the inclined wall construction lends itself very nicelyto economical manufacture since the inclined faces can be quickly required an at slight expense. It is to be understood that while I, have described the inclined surfaces as extending from the mlddie line of one of the vertical facesit is not essential that this line should be exactly in the middle of the vertical wall, and also that while I have described the inclined surfaces as terminating respectively at the upper and lower corners of the opposite wall, it is not essential and indeed is somewhat preferred to terminate these ends of the inclined surfaces in the upper and lower surfaces of the ring closely adjacent the corner, as indicated for instance, by the double line at e in Fig. 1. By so doing, the full width of the vertical wall is sure to be retained and is not likely to be worn down to permit of the flow of gas to the inner porac tions of the groove.

In the modification of Figs. 3, 4 and 6,

(ground oil at the exact angle the two inclined surfaces are separated .by an intervening horizontal rectangular surface 9 which improves the fit of the members of the joint. I claim: 7 V V A piston ring having each of its ends provided with twoinclined surfaces whose inclinations are in opposite directions and transversely of the ring, both of said surfaces extending from approximately the middle of one vertical wall of the ring and thence to a point adjacent theopposite upper and lower corners respectivel thereof, and a horizontal rectangular sur ace intervening between the two inclined surfaces and-having one of its edges at the. middle of the vertical wall in which said inclined surfaces begin.

In witness whereof I hereunto subscribe my signature.

JOHN E. PRUYN. 

